I am a novice too...I guess...but I've never heard of a break-in kit and I've bought Kimbers...which I don't feel like they've needed to be broke it. My AR is a Sig516...wish I had got the 716, but the dude talked me out of it.

They can run 80-90 bucks, and they don't do anything special.

Some of them have an abrasive bullet which I think can actually hurt a non-crome lined barrel.